This section provides background information related to the present disclosure which is not necessarily prior art.
There are numerous techniques for monitoring presence of an object using a two-body arrangement. A smart phone or other monitoring device can be programmed to communicate by radio or wireless communication protocol with a monitored mobile device, for instance. The monitored device can be a child bracelet and the monitoring device communicates with the bracelet and provides an alert when the bracelet moves out of range. A parent could use the arrangement to keep track of their child at a grocery store or amusement park using such a system.
There are numerous shortcomings to such two-body arrangements. A first shortcoming for most or all conventional arrangements is that both devices must be proximate each other in the first place. Initial connection is required for most or all conventional devices, and so the monitoring device would not generate an alert indicating that an already distant device, not first sensed in range, is not proximate. Rather, the conventional arrangements require that the devices be proximate and in initial communication with each other, and an alert is provided when the link is broken.
As another shortcoming, if the user leaves the monitoring and monitored devices in the same place, the user would not receive a notification that they are leaving a space without the monitored device.